STRUCTURE AND SOLID-STATE PROPERTIES OF THE CONDUCTIVE SALT OF (PHTHALOCYANINATO)COBALT, COPC(ASF6)0.5

A conducting crystal of (phthalocyaninato)cobalt hexafluoroarsenate Co Pc(AsF6)0.5 is prepared by an electrochemical method. Temperature-depe ndent electrical conductivity of & and 9.4 GHz shows that CoPc(AsF6)0. 5 is a narrow-gap semiconductor with activation energies of 327 K for dc and 138 K for 9.4 GHz. Thermoelectric power is +40 muV/K - +50 muV/ K in the range 100-300 K. The sign of the thermoelectric power is cons istent with our earlier spectroscopic result that Pc ring is mainly ox idized contrary to the analogous material CoPcI. Optical spectrum alon g the c axis exhibits strong and weak peaks at 0.29 eV and 1.2 eV. Mag netic susceptibility is composed of a Curie-Weiss part with C = 0.056 emu mol-1 and a nearly temperature-independent part with the magnitude of 5 X 10(-4) emu/mol. All these data indicates the localization of h oles (U>4t) like in (TMTTF)2X and Ag(DMe-DCNQI)2. This localization se ems to be related to the exchange interaction between the unpaired d-e lectron on Co and the pi-electron on macrocyclic ligand.